Foreign ministers of the Gulf Cooperation Council have urged embattled Yemeni President Ali Abdullah Saleh to transfer his powers to his vice president, as tens of thousands of anti-government protesters rallied in Yemen's capital, Sana'a.

The foreign ministers of Saudi Arabia, the UAE, Qatar, Oman, Kuwait and Bahrain met in Riyadh Sunday to review their mediation efforts.

The GCC said after the meeting that it is calling for talks between Yemen's government and opposition leaders based on the principle that Mr. Saleh would hand over his powers. It is also calling for the formation of a national unity government led by the opposition that would prepare the country for constitutional reforms and new elections.

President Saleh had initially accepted an offer by the GCC for talks between representatives of Yemen's government and opposition groups. But the Yemeni president rejected the offer on Friday after Qatar's prime minister said the GCC hoped to reach a deal with him that called for him to step down.

Clashes between Yemeni security forces and opposition activists turned bloody in Taiz on Saturday. Medics say at least 13 people were wounded when security forces opened fire and used tear gas on protesters. Protesters blocked traffic and set cars on fire in cities including Aden and the capital, Sana'a.

On Friday, witnesses in Taiz said at least four people were killed and dozens were wounded in unrest.

Some demonstrators were apparently angered by President Saleh's rejection of the GCC proposal.

For the past two months, anti-government protesters have been calling for an end to his 32-year rule. President Saleh has offered to resign, but only after new elections are held.

Some information for this report was provided by AP, AFP and Reuters.

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